The correct answer is: Health.
The Swachh Bharat Mission (SBM), also known as the Clean India Mission, is a national campaign launched by the Government of India on 2 October 2014. The mission aims to achieve universal sanitation coverage in India by 2019, and to make India open defecation free (ODF) by 2019.
The SBM has the potential to improve the health of Indians in a number of ways. First, it will reduce the incidence of diarrheal diseases, which are a major cause of child mortality in India. Second, it will reduce the risk of exposure to vector-borne diseases, such as malaria and dengue. Third, it will improve the quality of life for Indians by reducing the prevalence of open defecation, which is a major source of environmental pollution and a health hazard.
The SBM is a complex and ambitious project, but it has the potential to make a significant impact on the health of Indians. The mission has already made progress in reducing the number of people defecating in the open, and it is expected to achieve its goal of making India ODF by 2019.
The other options are incorrect because they are not directly related to the Swachh Bharat Mission. Education and income are important factors in the HDI, but they are not directly affected by the SBM. The environment is affected by the SBM, but it is not the primary focus of the mission.